1. Field of the Invention
The present invention relates to a composite image forming apparatus having a plurality of functions such as a copying function, a network scanner function, and a network printer function and a control method therefor.
2. Description of the Related Art
There is a composite image forming apparatus having a plurality of functions such as, in addition to the regular copying function, the network scanner function for externally transmitting an image read by a scanner by attaching it to an electronic mail and the network printer function for printing and outputting an image according to an image signal input externally.
In such a composite image forming apparatus, the copying function can be used immediately as a standard function. However, the network scanner function and network printer function may be permitted to use them under the condition that a user optionally purchases them when necessary.
However, even if the user optionally purchases the network scanner function or network printer function, thereafter he has few chances to use it, thus he may be required for useless expenses.